Excavating-machine.



No. 856.965] PATENTED JUNE 11 1907.

P. J. LEWIS.

'EXGAVATING MACHINE.

APPLIOATION FILED OUT. 27, 1906.

W1 TNESSES: [NVE/VTOR as PAW-AW" w M By mm e which are secured to the boom der.

FITZ JAMES LEWIS. OF EMPIRE, PANAMA.

EXCAVATlNG-MACHINE.

Specification of Letters Patent.

Patented June 11, 1907.

Application filed October 27,1906. Serial No. 340,885-

To all whom it may concern:

Be it knownthat I, FITZ JAMES LEwIs, a citizen of the United States, residing at Empire, in the Canal Zone, Panama, have invented certain new and useful Improvements in Excavating-Machines and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to-make and use the same.

This invention relates to excavating machines provided with dippers; and it consists of novel mechanism for operating the latch of the dipper discharge door, as hereinafter fully described and claimed.

In the drawings, Figure 1 is a side view of portions of an excavating machine showing the mechanism for operating the latch partly in section. Fig. 2 is a front view of the drum and the other parts which are mounted on the drum shaft.

A is the boom of an excavating machine of any approved construction; and B is the dipper provided with a handle I) for operating it.

C is the discharge door of the dipper, and c is the latch which drops into position automatically by a spring or by ravity, and which normally locks the said door in its closed position. D is a flexible connection, such as a wire rope, attached to the said latch, and d is a guide tube for the said rope secured to the dipper handle. This tubular guide is better than guide sheaves as it is less likely to get broken or to get out of or- The guide tube is held in position by staples d or other similar fastening devices, so that it can be slid and adjusted longitudinally of the dipper handle.

E is a shaft which is mounted in bearings A, and e is a winding drum which is secured to the said shaft and which has the end of the rope D wound upon it and secured to it.

F is a collar which is adjustable on the shaft E, and which is provided with a setscrew f or other similar fastening device for securing it to the said shaft after its position has been adjusted. A tension spring f is provided for holding the rope D taut to a prearranged degree and so that the latch may close freely. One end of this spring is secured to the boom, and its other end is secured to the collar F. The main portion -is pivoted on the shaft E. A

of the spring is coiled spirally about the shaft E.

G is a ratchet toothed wheel which is secured to the drum 6, and g is a lever which awl g is pivoted at the free end portion of the lever g for engaging with the teeth of the ratchet wheel. An arm H is secured to the pawl or to its pivot, and is provided with a red It which is slidable in a guide it which projects from the lever g. A spring I is coiled about the rod h, and operates to hold the pawl normally out of engagement with the wheel G. An operating lever i is pivoted to the boom A, and i is a flexible connection, such as a cord or wire, between the said lever and the o erating red It. A spring J is arranged in t e length of the connection 11, and j is a uide sheave for the said connection carried by the lever 9.

K is a steam or other motor cylinder secured to the boom A by suitable brackets and provided with a piston 7t and a pistonrod is. The front cover 2 of the cylinder forms a guide for the piston-rod, and the piston-rod is operatively connected with the ever g by means of a in 3 which engages with a slot 4 in the said ever.

' L is a return spring for the piston arranged in the front end of the cylinder K, and 5 are buffer springs for the 'piston arranged in the rear end of the said cylinder. The cylinder is provided with a series of exhaust ports 6 in its front end portion, and 7 are plugs for closing such of these ports as are not in use for the time being. by the piston which uncovers the open exhaust port; and the length of the stroke of the piston is varied by selecting an appropriate port and closing the others with plugs.

M is the steam supply pipe connected to the rear end of the cylinder K, and provided with an inlet valve m. The operating lover;

of this valve m is connected with the operating lever i by means of a rod m or other suitable connectmg device.

The exhaust is effected IuO N is a small relief valve connected to the rear end of the cylinder, and n is a tappet bar which operates the said valve. This bar is adjustably connected to the piston-rod 7c so that the valve .N is held open while the piston is being pushed back by the return spring and until about the time the piston strikes the buffer springs.

P is the platform for the operator in charge. of the excavating machine. This platform is secured to the boom in the usual position, and the operating lever i is arranged conveniently with respect to it. A guide sheave p is supported from the boom to guide the rope D between the drum and the guide tube secured to the dipper handle.

The action of the parts is as follows: When the dipper is full and has been moved to a suitable position to dump its load, the operating lever i is moved by hand so as to place the pawl in engagement with the ratchet toothed wheel, and so as to open the steam supply valve m. The spring J permits the steam valve to be opened wide, after the pawl is in engagement with the wheel, and insures the engagement of the said pawl with the teeth of the wheel before the steam valve is opened. The piston is forced forward in the cylinder, and turns the drum for a portion of a revolution by means of the lever and pawl, and the latch of the dipper door is retracted by means of the rope which is wound on the drum. The operator shuts off the steam when he hears the steam issue from the exhaust port, and the piston is forced back by its return spring until it strikes the buffer springs. The small relief valve is held open during the greater part of the return movement of the piston, which takes place slowly so that a small relief outlet is effective. Under normal conditions the drum is free to revolve in each direction so that the rope is kept taut as the dipper is moved about and operated, and so that the latch may fasten the discharge door automatically, being moved by its latch spring or by gravity.

hat I claim is:

1. The combination, with a dipper boom, and adipper provided with a discharge door and a latch therefor; of'a revoluble shaft carried by the said boom, a collar secured to the said shaft, a tension spring connected to the said collar and operating to revolve the said shaft in one direction, a drum secured on the said shaft, and a flexible connection wound on the said drum and connected with the said latch.

2. The combination, with a dipper provided with a handle and having a door and a latch therefor; of a guide tube secured to the said dipper handle, and a flexible connection slidable in the said tube and connected with the said latch.

3. The combination, with a supporting I boom, a dipper provided with a door and a gaging with the said wheel, a motor cylinder 's latch therefor; of a revoluble drum, a flexible connection wound on the said drum and connected with the said latch, means for keeping the said connection taut, a ratchet toothed wheel for revolving the said drum, a pivoted lever provided with a pawl for ensecured to the said boom and provided with a piston operatively connected with the said lever, a steam connection for moving the piston in'one direction, and a spring for. moving the piston in the reverse direction.

4. The combination, with a dipper provided with a door and a latch therefor; of a revoluble drum, a flexible connection wound on the said drum and connected with the said latch, a ratchet toothed wheel for revolving the said drum, a pivoted lever provided with a pawl for engaging with the said wheel, a tension spring for holding the said flexible connection taut, means for normally holding the said pawl out of engagement with the said wheel so that the said drum is free to revolve in each direction, and means for placing the said awl in engagement with the said wheel and or actuating the said lever.

5. The combination, with a supporting boom, and a dip er provided with a door and a latch therefbr; of a revoluble drum, a flexible connection wound on the said drum andconnected with the said latch, means for keeping the said connection taut, a ratchet toothed wheel for revolving the said drum, a pivoted lever provided with a pawl for engaging with the said wheel, a motor cylinder secured to the said boom and provided with connections for operating the said lever, means for moving the said pawl into and out of engagement with the said wheel, and means for supplying pressure fluid to the said cylinder after the said pawl has been placed in engagement with the said wheel.

6. The combination, with a supporting boom, and a dipper provided with a door and a latch therefor; of a revoluble drum, a flexible connection wound on the said drum and connected with the said'latch, means for keeping the said connection taut, a ratchet toothed wheel for revolving the said drum, a pivoted lever provided with a pawl for engaging with the said wheel, a motor cylinder secured to the said boom and provided with connections for operating the said .lever, means for normally holding the said pawl out of engagement with the said wheel, a valve for,

supplying pressure fluid to the said cylinder, a single operating lever, and connections between the said valve and operating lever and between the said pawl and operatinglever whereby the said pawl is operated only when in engagement with the said wheel.

7. The combination, with a dipper provided with a door and a latch therefor; of a revoluble drum, a flexible connection wound on the said drum and connected with the said latch, a ratchet toothed wheel for revolving'the said drum, a pivoted lever pro vided with a pawl for engaging with the said wheel, a motor cylinder and connections for operating the said lever, said cylinder being provided at one end with an exhaust port connected to the other end of the said cylin- '10 tion Wound on the said drum and connected with the said latch, and a tension spring which winds the said drum in one direction and thereby holds the said connection taut while the dipper is bein" operated.

signature in the presence of two witnesses. FITZ JAMES LEVIS.

\Yitncsses:

F. H. SHEIBLEY, E.

J. FREDERICK.

In testimony whereo I have affixed my 15 

